Electric stop motion for looms



July 15, 1930. T. C. WAGNER 1,770,562

ELECTRIC STOP MOTION FOR LOOMS Filed Sept. 4, 1928 2 Sheets-Sheet l July 15, 1930.

T. C. WAGNER ELECTRIC STOP MOTION FOR LOOMS Filed Sept. 4, 1928 2 Sheets-Sheet 2 E 6' I J M Patented July 15,1930

THEQIDOR CUR! WAGNER, bF CHEMNITZ, GEBMANY nnnc'rnrc sror mo'rron r013. Looms Application filed September 4, 1928, Serial Ho. 303,8 60, and in Germany Kay 7, 1928.

' My invention relates to electric stop motions 'of the type used in looms. In this art the stop motion has an important part, since it is indispensable for an economically satisfying operation of the loom to have it stopped as quickly as possible upon occurrence of a breakage of a warp-thread. Furthermore, care must be taken to remove the warps and to fit up new warps asquickly as possible.

Electric stop motions are to be referred over mechanical ones due to their slmplicity. The electric stop motions hitherto known, however, have great drawbacks because specially punhed lamellas are required which not only complicate the entire mechanism, but also render the attendance difiicult, be-

cause upon tearing, the thread must not only be drawn through the eye of the heddle but also through that of the lamella, this threading taking place at two different places and therefore-requiring at least a double manipulation. In the same manner the work of removing and filling-up of new warps is multipliedL The required reliability is further not attained by follo the proposal to design the upper or lower ar of the leaf as a conductor and to arrange therein and insulated therefrom another conductor, which both conductors are interconnected owing to the position the and eye of the heddle referred to takes upon breakage of a thread, so that when current is supplied to the conductors, a

circuit is closed that stops the loom.

rangements of this Epe the closure of the circuit sometimes fa My invention has for come these drawbacks.- tained primarily by embedding two conductors in the upper heddle bar these conductors being insulated from one another and from v a the bar and the upper edges of which project beyond the bar in such a manner that they its object ,to overare conductively connected by the upper eye of the heddles when the latter are hanging therefrom. Advantageously the heddle bar has a U-shapedcross section and is open on its upper side, ranged symmetrically to the vertical middle In ar- This object is obwhilst the: two conductors are ar-' plane of the bar. This arrangement secures a reliable conductive connection of the two conductors by the upper eyes ofthe heddles in the hanging position. This effect may be further improved by making the upper portion of the eyes of the heddles that establish this electric contact being roof-shaped, so that the eyes ride so to speak on the two conductors and interconnect them with cer-' tainty.

The leaf of such a loom is provided with suitable contact pieces that in a determined position of the leaf close a circuit through the conductors. Now, as an accumulation of dust on all parts of the loom is unavoidable, the danger exists of the contact pieces failing to function. In order to overcome this trouble, according to my invention, each of the resilient contact pieces raising and lowering with theleaf, ends in a downwardly directed point which comes into correct conductive contact with the appurtenant stationary contact piece even if the latter is covered with wool dust or the like.

In order that my invention may be more easily understood, some preferred embodiments of the same are illustrated by way of example in the drawings which accompany and form part of this specification. In these drawings Figure 1 shows a lea'f'in front view,

Figures 2 to 5 are sections through the upper bar in different positions, on an enlarged scale,

Figures 6 to 9 are similar sections, showing eddles having modified upper eyes, and

igur

cs 10 and 11 show a detail in two different positions. a

While the leaf 12 is of the usual design, the upper bar 13 has a U-shaped cross section and embedded in it two conductors 14 and 15. These conductors are arranged s etricall to the vertical middle plane 0 bar 13 and t eir upper edges project so far beyond the latter that when the upper eye 16 of one of the heddles 17 rests on the bar 13, as is to be seen from Figures 2, 4, and 5, a conductive connection is established between the two conductors 14 and 15.

The conductor 14 is conductively connected cuit including the stopping means position,

creased work or attention,

to a resilient contact piece 18 and the concontact pieces 20 and 21, respectively, whic are located so as to establish contact and to cause a circuit to be closed through the conductors 14 and 15 when'the leaf is in its lowermost position. The circuit thus closed by the interconnection of the conductors 14 and 15 further includes the usual electric means (not shown) serving to stop the loom.

The described device operates as follows: As long as the warp-threads one of which is denoted by 22, are intact, an electric connection is established between the conductors 14 and 15 by the upger eye 16,-when leaf 12 raises, as shown in igures 2, 4, as the thread 22 exerts a downward pull on the heddle 17. As soon however, as the leaf has passed, in lowering the middle position, the thread 22 will act against the downward movement of the heddle, so that the upper eye is lifted and the connection between the conductors 14, 15 interrupted, as shown in Figure 3. Now, as the contact pieces 18, 19, 20, 21 are in re; spective connection only with the leaf in the lowermost position, while all of the eyes 16 normally have the lifted position shown in Figure. 3, the circuit is permanently interrupted. en however a warp-thread breaks, the eyes remain in the last-mentioned giosition upon the leaf 12 raising. Upon,

owever, the leaf 12 lowering, no upward push is exerted on a heddle the thread of which is torn, so'that the respective eye 16 will remain in the ition shown in Figures 2, 4, and 5, even w en the leaf has attained its lowermost see Figure 5. At this instant however the contact pieces 18, 19, 20, 21 come into contact with each other, current is fed to the conductors 14, 15, and as these conductors are conductivel interconnected b' the eye 16 of the hedd e 17 of the broken t read, the ciris closed, the latter is actuatedand stopsthe loom. As soon as the operator has repaired the broken thread the loom operates anew as above descri until with the next breakage of a thread the stopping device acts in the same manner.

As can be seen from the foregoing, the described arrangement is extraordinarily simgge and relia Is in action, as the upwardly rected contact points of conductors 14, 15 and egos 16 are not rendered inoperative b fibre ust and the like. Besides, the atten ance of the loom does not uire any inas it differs in no not fitted with a n the embodiment illustrated in Fi res 6 to ,9 the upper portion of the eye 16 0 each heddle 17 has not a round shape, as has been way from that of a loom sto ping mechanism.

indicated in each of the Figures 2 to 4 and' insulation and t hitherto usual, but according to my invention this portion has a roof-shaped configuration; Therefore, as soon'as the heddle is hanging from the bar 13, as shown in Figures 6, 8, and 9, the two legs 23, 24 of this roofshaped upper eye portion come to rest on the projecting conductors 14, 15 and interconnect them electrically. Any failure of this conductive connection is absolutely impossible, ason the one hand these legs 23, 24 are resilient and have on the other hand the tendency to center the eye relativel to the two conductors, so that their mi dle plane always coincides with that of the eye. Because this is the case, a conductive connection between the two conductors is also warranted, assoon as they become energized by the closure of the contact piece 18,20 and 19, 21. The an 10 formed by the legs 23, 24 depends on c section of the upper bar 13 and of that of the two conductors. Generally an angle of about degrees will be of advantage, so

that the roof corresponds to an equilateral tri-' angle whereby a particularly satisfyin" contact is warranted. Of course, I do not clinfine my invention to this modification, in the conit includes any type of roof-sha d' trarhy, con guration of the upper eye of heddles t at establish electric contact.

As to be seen from Figures 10 and 11, the

electric contact pieces 18, 19 fixed on leaf 12 may further end in a point 25 and 26, respectively. This shape establishes a correct conductive contact between contact pieces 18, 19 and stationary pieces 20, 21 even in case fibre dust or the like has deposited on the latter, as the points 25, 26 penetrate even the thickest dust layer. Figure 11 shows one of the pairs of contact pieces 19, 21 in the closed position, in which the point 26 is urged by spring 27 against thev stationary piece 21 and thus establishes an absolutely certain conductive connection.

What I claim and desire to secure by Letters Patent, is

1. In an electric stop motion device for looms a leaf with an upper heddle bar of U-shaped cross section, two electric conductor bars embedded in said heddle bar insulated from each other and from said heddle bar, their upper rtions extending above the e heddle bar, heddles embracin and ri ing upon said conductor bars if unsupported, contacts moving with said heddle each other and from said heddle bar, their said heddle bar with their upper eyes upper portions extending s etricall a ove the insulation and the he dle bar, he dles embracing said heddle bar with their upper eyes and riding upon" said conductor bars ii'unsupported, the upper part of said eyes having the shape of aninverted V, re-

silient contacts moving vertically with said I heddle bar and electrically connected to said conductor bars, and correspondin fixed con- 19 tacts, said movable contacts establlshing electric connection with said fixed contacts if the frame is in its lower position. I

3. In an electric stop motion device for looms a leaf with an upper U-shaped heddle bar, tw0 conductor bars embedded in said heddle bar insulated from each other and from said heddle bar, their upper portions extending above the insulation and the heddle bar, heddles embracing said heddle bar 0 with their upper eyes and riding upon said 60 is in its lower position.

contact bars if unsupported, the upper part of said eyeshaving the shape of an mverted V, resilient pointed contacts moving vertically with'sa'id heddle bar and electrically connected to said contact bars, and correspending fixed contacts, said movable contacts establishing electric connection with saidafixed contacts if the frame is in its lower position.

4. In a device of the character described a leaf having an upper heddle bar of U-shaped cross section, twoconductor bars symmetri cally embedded in said heddlebar insulated fromsaid bar and from each other, their upper parts extending beyondthe insulation, resilient pointed moving contacts on said heddle bar, each contact being electrically connected to one of said conductor bars, stationary contacts corresponding to said moving contacts, and heddles with their upper eyes embracin said heddle bar and riding on said contact ars in unsupported position said eyes having symmetrical straight an inclined upper portionsfor making contact with said conductor bars.

' "5. In an electric stop motion device for looms, a leaf with an upper heddle bar, two electric conductor bars embedded in said heddle bar insulated from each other and from said heddle bar, heddles embracing said heddle bar with their u per eyes, said upper eyes being formed 0 an inverted V symmetrical with the longitudinal axis of said heddle, each leg of sai V being resilient and riding on one ofsaid conductors if unsu orted, contacts moving with said hedd e ar, andcorrespondin fixed contacts, said movable contacts estab ishing electrical connection with said fixed contacts if the frame In testimony whereof I afiix my signature.

GURT WAGNER. 

